The “IAV DrivePac EV80” exhibit is a compact unit that consists of an electric motor and two-speed transmission, commands little space in the vehicle and was designed to save as much weight as possible. Propulsion comes from an asynchronous motor with a continuous power output of 50 kilowatts delivering 150 newton meters of continuous torque, and with a maximum power output of 80 kilowatts delivering maximum torque of 300 newton meters.
The integrated two-speed transmission of planetary gear-train design makes efficient use of energy in providing a high level of axle torque over a wide speed range – significantly enhancing the ride comfort and efficiency of an e-vehicle: Whereas hill-climbing performance and accelerating power are improved in the lower speed range, maximum vehicle speed can be reached with the e-motor running at lower speeds.
Simulations show that the two-speed transmission improves hill-climbing performance by 88 percent with twelve percent less time needed to accelerate from naught to 100 km/h – the time taken to get from naught to 60 km/h is even cut by 32 percent.
Clear benefits are shown in the NEDC as well: Here, consumption falls by 16 percent. The DrivePac EV80 is designed for use in segment A (microcar), B (subcompact) and C (compact-size category).
The I2+2 engine cuts consumption in the NEDC by almost 14 percent
In the second exhibit, the I2+2 engine, IAV’s developers have intelligently modified the concept of cylinder deactivation: They combine two two-cylinder engines with a swept volume of 0.8 liters each, giving them a firing interval of 360 degrees and interconnecting them by an auxiliary shaft and two gear pairs. At low load one of the two sub-engines is deactivated and completely disconnected from the powertrain – this avoids the high friction losses associated with classic cylinder deactivation because the sub-engine that is shut down still has to be motored. The second engine is automatically activated when it is needed.
The new concept reduces engine friction torque by 22 percent in the engine speed range relevant to consumption. This cuts consumption of the I2+2 engine in the NEDC by 13.7 percent, equating to 19 grams of CO2 per kilometer. In cycle 2, it falls by 6.2 percent (9 grams of CO2 per kilometer) – this cycle involves a different load distribution and more changeovers between the two and four-cylinder operating modes than in the NEDC.
IAV miniECUS: Module for virtual test benches for simulating the overall vehicle
Also on display at IAV’s booth: IAV miniECUS (Electronic Control Unit Stimulus), an HiL environment that IAV has developed. At Aachen, IAV’s experts will be demonstrating how IAV miniECUS can be combined with an engine control unit and a diesel engine system model under the GT suite. IAV is the first company from the automotive industry to pursue the innovative concept of using the GT tool platform for physical HiL applications.
Capable of incorporating physical models of the combustion engine and of exhaust gas aftertreatment, a “virtual test bench” of this type provides the basis for developing operating and control strategies that reduce consumption and CO2 emissions – without involving prototypes. IAV’s developers have the long-term goal of using models of the entire vehicle as a way of shortening the time needed on the test bench and of speeding up the development process.
For each of the exhibits an IAV expert will be on hand in Aachen for interviewing and answering technical questions: Lutz Stiegler (DrivePac EV80), Dr. Jörg Ross (I2+2 engine) and Winfried Schultalbers (IAV miniECUS).
Presentation on the noise-controlled diesel engine
In a presentation, Berlin University of Technology will be showcasing the concept of a noise-controlled diesel engine developed in cooperation with Magdeburg Otto-von-Guericke University and IAV. The result of an FVV research project, it uses the engine’s structure-borne sound signals to obtain information on combustion, injection and noise emissions. This can be used for managing the engine on the basis of structure-borne sound – current approaches do this by using cylinder-pressure sensors which, however, are not entirely suitable for application in volume production on account of high costs and a lifespan that needs to be improved.
In their joint FVV research project, both research institutes and IAV have developed an intelligent way of processing the engine structure-borne sound signals that permits new strategies for controlling a diesel engine – making it possible to lower fuel consumption, cut emissions and optimize noise behavior. With this new approach, the project partners have achieved the performance of cylinder-pressure-based engine management without having to tolerate its specific drawbacks. In an example application they have also demonstrated that this approach is suitable for use in practice.
This is IAV:
Employing over 5,000 members of staff, IAV is one of the world’s leading providers of engineering services to the automotive industry. The company has been developing innovative concepts and technologies for future vehicles for over 25 years. Core competencies include production-ready solutions in all fields of electronics, powertrain and vehicle development. Clients include all of the world's premier automobile manufacturers and suppliers. In addition to development centers in Berlin, Gifhorn and Chemnitz, IAV also operates from other locations in Europe, Asia as well as North and South America.